Genetic variations may influence the effect of magnesium on diabetes risk

The preventive effect of adequate magnesium intake on developing type 2 diabetes appears to vary depending on genetic variations and ethnicity, reports a new US study.

The observational study analyzed magnesium intake, cases of type 2 diabetes, and specific genetic variations in 7,287 African-American women and 3,285 Hispanic women between the ages of 50 and 79 (1). The study results showed that the participants’ risk of developing type 2 diabetes varied depending on magnesium intake, genetic variations (polymorphisms) in magnesium-related ion channel genes, and ethnicity. For example, among Hispanic women with low magnesium intake, certain single-nucleotide polymorphisms were associated with an increased risk of diabetes. Among African-American women with high magnesium intake, one specific gene variation was found to have a diabetes-protective effect.

The researchers commented that earlier large prospective studies of men and women have already associated increased magnesium intake with a lower risk of type 2 diabetes (2). The absorption of magnesium (Mg2+) relies on ion channels coded by genes of which several single-nucleotide polymorphisms are known. Such genetic variations in ion channels can significantly influence the body’s magnesium supply and glucose metabolism, and are associated with the risk of developing type 2 diabetes (3). A sufficient intake of magnesium may partially compensate for magnesium deficiency caused by such genetic mutations. Further confirmation of these recent observations is needed from future mechanistic studies, the scientists noted.

1. Chan K. H. K. et al. Genetic Variations in Magnesium-Related Ion Channels May Affect Diabetes Risk among African American and Hispanic American Women. Journal of Nutrition. Published online January 2015.
2. Lopez-Ridaura R. et al. Magnesium intake and risk of type 2 diabetes in men and women. Diabetes Care. 2004; 27:134–140.
3. Song Y. et al. Common genetic variants of the ion channel transient receptor potential membrane melastatin 6 and 7 (TRPM6 and TRPM7), magnesium intake, and risk of type 2 diabetes in women. BMC Med Genet 2009; 10:4–15.